[unreadable] The long-term goal of this research is to determine the crystal structures of various constructs of endophilin-A2, which will augment existing in vivo and molecular biology studies of the mechanisms involved in the complex and highly regulated cellular process of endocytosis. Endophilins are an SH3 domain containing family of proteins that function in processes such as clathrin-mediated endocytosis, protein trafficking, cell architecture maintenance, cell proliferation and differentiation, and in the immune response. There are no available structural data for these proteins. In this proposal we will purify recombinant rat endophilin-A2 from E. coli and initiate crystallization screens. To facilitate protein crystallization we will identify stable domains by limited proteolysis. Finally, crystal growth will be optimized to generate welldiffracting crystals to allow for structural determination studies. Structural information will lead to insights into how endophilin-A2 functions, both alone and with its various protein binding partners. This will increase our understanding of basic endocytic processes, and how alterations in these processes can result in disease states. [unreadable] [unreadable]